The northernmost stretch of NH 1 falls in the Indian state of Punjab. It initiates at the Wagah Border between India and Pakistan, at the Attari village and runs 30 km down to the city of Amritsar. From there, it passes through the districts of Kapurthala, Jalandhar, Ludhiana, Sangrur and Patiala. The cities of Kapurthala, Sangrur and Patiala, however, do not fall along the NH 1. In Patiala district, the highway passes through the town of Rajpura, which has gained prominence due to its important location on the GT Road.

This stretch of NH 1 was witness to the mass-movement and selective massacre of refugees across what is today the border between India and Pakistan, during the Partition of India.

After Sonipat, the highway enters its last leg, into the national capital Delhi. The minor stretch of NH 1 in Sonipat district, leading up to the Delhi border, has been witnessing massive real-estate development along it.

Delhi marks the last leg of the NH 1. It enters Delhi at the Singhu Border in the northern district and passes through all of North Delhi up to the ISBT Kashmiri Gate. There it merges into the Ring Road and proceeds beyond as NH 2, up to the Bangladesh border. In Delhi, the region through which the highway passes is the most underdeveloped and encroached district of the city. It is mostly industrial and ill-planned. The Guru Tegh Bahadur Memorial falls along the NH 1 close to the Singhu Border, in Delhi.

NH 1 presently has 4 different spur routes designated as 1A, 1B, 1C and 1D. Except for 1A, all these spurs are entirely within the state of Jammu and Kashmir. These spurs are strategically important as they connect remote cities and towns in the Himalayas with the rest of India.